This invention relates to apparatus for controlling the flow of combustion gases through a furnace conduit, and more particularly to a damper shiftable into and out of the conduit and having a damper support through which a coolant fluid may flow to cool the support and damper.
As combustion gases are produced and flow through various conduits in a furnace, it is often necessary either to close or open the damper to selected degrees to provide a control of the flow of such gases through the conduit. Various styles of dampers have been designed in the past, with some of previous dampers attempting to provide circulation of coolant fluid about the damper or through coils in the damper in an attempt to cool the same. These have not been altogether satisfactory in that in such previous devices the coils or conduits for passage of coolant fluid have been metallic and have been positioned in the damper in such a manner that they are subjected to the direct effects of the combustion gases. Further, such previous devices usually have provided merely for the recirculation of a coolant fluid and have not provided for any flow of coolant fluid over the faces of the damper to aid in cooling the same.
In such previous dampers there has been little, if anything, to shield metallic supports for the damper from the direct effects of combustion gases and thus they have been weakened and detrimentally affected by the combustion gases.
A general object of the present invention is to provide novel apparatus for controlling the flow of combustion gases through a furnace conduit including a damper and damper support from which a flow of coolant fluid may pass to cool the damper and support, which apparatus is so constructed as to overcome the disadvantages of prior devices as set out above.
More specifically, an object of the invention is to provide a damper constructed of refractory material mounted for shifting into and out of the conduit and having a metallic damper support connected to and supporting the edge of the damper opposite that edge which is shifted into and out of the conduit, with the damper support having a coolant fluid flow passage therein and apertures extending between the passage and exterior of the support through which a flow of coolant fluid may flow to the exterior of the support to cool the damper and support.
A further object is to provide such novel apparatus in which the damper has coolant fluid passages defined therein and extending therethrough communicating with the passage in the support to permit a flow of coolant fluid to pass through the damper.
A still further object is to provide such novel apparatus which includes a housing extending laterally of the conduit which has side and end walls so positioned as to receive and enclose the damper support throughout operation of the damper, thus to shield the damper support from direct effects of the combustion gas throughout operation of the damper.
Yet another object of the invention is to provide such apparatus which includes novel means for supplying a flow of coolant fluid under pressure to the damper support and damper housing.
These and other objects and advantages will become more fully apparent as the following description is read in conjunction with the drawings.